There are a number of ways to communicate handwritten information electronically. One alternative is to write the information on a sheet of paper and thereafter to send the information via a fax machine. An alternative way of sending handwritten information electronically is to scan it in and to send it electronically via, for example, electronic mail or using the mobile telephone network. A disadvantage of both methods is that two steps are required to enter the handwritten text electronically. In a first step the user writes the text on a base and in a second step the handwritten text is converted into electronic format via optical reading in the scanner or the fax machine.
International Patent Applications WO 01/48591, WO 01/48678 and WO 01/48685 describe user units and methods for recording and communicating handwritten information electronically. A user unit of the type described in said WO documents has a memory in which the information that has been recorded by the user unit is stored. The user unit can be arranged to send information by wireless means to, for example, a mobile telephone or a personal computer, from which the information is forwarded to the correct recipient, typically via an information management unit in the form of a network server or the like. An example of information that can be recorded by the user unit is a handwritten message, a signature or a handwritten address on a form.
In several cases, it can be advantageous to save the information recorded by the user unit for use at a later occasion. This is the case, for example, if the user has recorded his personal details and selections on an order form and wants to add to the order at a later time. It is then advantageous to be able to add to the previously entered information. Similarly, the user can choose to delay sending a handwritten message to a recipient, in order to be able to add to and/or dispatch the message at a later time.
A user unit for recording handwritten information is advantageously hand-held and is a typical home electronics product. In order to keep the price of the product down, this is therefore provided with a relatively small internal memory unit.
This means that the amount of information that can be stored in the user unit is relatively limited and that information that has been recorded by the user unit must be deleted after a while. It is, however, difficult to know what information can be deleted and what should be saved. If we choose to make the memory unit large in order to reduce the need to delete so often, there is the risk that the user unit will be undesirably expensive.
Within the technical field of hand-held user units for recording information, the provision of replaceable memory cards for a hand-held user unit is described in WO 97/15896. The storage capacity of the user unit can thereby be increased as required, however at the expense of a reduction in user-friendliness, increased cost to the user, a reduction in the freedom of design of the user unit, increased risk of operational disturbances caused by the ingress of dust, moisture, etc.
Within the technical field of personal computers, the provision of external storage memory via a network connection is already known, for example for security back-ups of files on the personal computer's hard disk or for file sharing, such as, for example, described in U.S. Pat. No. 6,192,165 and U.S. Pat. No. 6,003,047.